Brush-holder for dynamo-electric machines



(No Model.) 2 SheetsSheet '1.

' E. THOMSON 8v W. O. WAKEFIELD. BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES.

No. 462,973. Patented Nov. 10, 1891.

7 4 g 31- Q gl A *4 LL WIT IZZEEL l h/E lm i (No Model.) 2 Sheets-Sheet 2 E. THOMSON & W. 0. WAKEFIELD. BRUSH HOLDER FOR DYNAMO ELECTRIC MACHINES.

No. 462,973; Patented Nov. 10,1891.

UNITED STATES PATENT OFFICE.

ELIHU THOMSON, OF SIVAMPSOOT", AND \VILLIAH O. \VAKEFIELD, OF

' LYNN, MASSACHUSETTS.

BRUSH-HOLDER FOR DYNAMO -ELECTRIC MACHINES.

SPECIFICATION forming part of Letters Patent No. 462,973, dated November 10, 1891.

Application filed February 20,1891. Serial No. 382,153. (No model.)

To all whmn it may concern.-

Beit known that we, ELIHU THOMSON, a citizen of the United States, residing at Swampscott, in the county of Essex and State of Massachusetts, and WILLIAM O. WAKEFIELD, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented a certain new and useful Improvement in Brush-IIolders for Dynamo-Electric Machines, of which the following is a specification.

Our invention aims to secure a holder for the commutator-brushes of a dynamo-electric machine, generator, or motor which permits ready adjustment of the brush-carrying arms bodily toward and away from the commutator, ready access to the brushes, and simplicity of construction in general.

To this end it consists in certain novel parts and combinations, which will be clearly understood from the following specific description and are illustrated in the accompanying drawings, wherein- Figure 1 is a perspective view showing our invention. Fig. 2 is an end view of one of the brush-carrying arms, and Figs. 3 and 4 are details of specific parts.

Encircling the shaft of the armature is a yoke R R, made in two parts, permittingits ready removal, which stands in ourinvention as a support for the brush-arms and brushes and may be replaced by other parts serving the same purpose. I

From opposite sides of the yoke extend projections W W, or studs as we call them herein, which are either insulating in character or insulated, and will usually consist of insulating-sleeves slipped over inner rods or pins on the yoke, handles H H being provided for shifting the yoke around the shaft. These studs W are made square or of other angular form in cross-section, the only essential point being that their shape is such as to hold the brush-arms from rotating thereon, while permitting adjustment toward and away from the commutator. The brusharms are attached to the studs by clamps O, embracing the latter and secured in place by nuts 07.. Each arm comprises a box or socket Q for the brush and brackets or braces S S on opposite sides of the box, leaving a clear open space in line with the brush.

Upon the brackets are pivoted on pins P P swinging followers D D,shaped as shown, and each provided with a ring 0 or other hand-hold, while at their free ends are at tached rocking springs F, having flanges f, spanning the brush T, of carbon, or carbon and metal, in any of the forms now used.

- These followers press the brush into engagement with the commutator, and for that purpose springs E E are provided, attached to the arm at c c and to lugs s .9 upon the followers, which project out slightly to one side, so that the followers can be thrown over a dead-center, as indicated in dotted lines, Fig. 2, and held there by the springs, thus permitting the ready removal of the carbon brushes or examination of the commutator.

In order to insure a good contact with the brush, we attach two springs E E, Fig. at, to the box, whose free ends press laterally against the sides of the brush.

The brush-arms as a whole may be adjusted lengthwise on studs IV, as may be found desirable, according as thelength of the brushes changes, and the arrangement of followers described keeps the brush firmly in contact with the segments even though the motors be subjected to considerable jar, as in railwaywork, thus avoiding sparking.

\Vhat we claim as new, and desire to secure by Letters Patent, is-

1. The combination of the commutatoryoke having radially-proj ecting pins, insulating-sleeves on said pins, clamps radially adjustable on said sleeves, and brush-holders carried by said clamps.

2. The combination of the commutatoryoke having radially-projecting pins, insulating-sleeves of non-circular cross-sections on said pins, clamps radially adj ustable on said sleeves, and brush-holders carried by said clamps.

8. The combination of a commutator-yoke having insulating or insulated studs of angular cross-section with the brush-arms having clamps embracing the studs and adjustable lengthwise thereon and one or more springlowers having independent actuating-springs actuated followers pressing the brushes and each acting to press the brush against against the colnmutators. the commutator. 2O

4. The combination of a commutator-brush 7. The combination of the brush-arm and 5 holder having a socket, a brush movable brush with the followershaving pivotal beartherein, abrush-pressing arm movable toward ings on opposite sides of the brush and and away from such brush, and a spring actadapted to swing down beside one another ing upon said arm to hold it upon either side upon the brush, pressing the latter into en- 25 of a dead-center. gagenient with the commutator, as described.

10 5. The combination of a brush-carrying In testimony whereof we have hereto Set arm having a box or socket for the brush, a our hands this 17th day of February, 1891. pivoted follower, and a spring acting to hold y 1 i the follower when swung to either side of a ELHIU HIOMSON' d ead c em as set forth. WILLIAM O. WAKEFIELD. I 5 6. The combination of a brush-arm having lVitnesses:

a box or socket, with the brush set in such JOHN W. GIBBONEY,

socket, and the independently-pivoted 'fol- BENJAMIN B. HULL. 

